Lipid molecular species composition of thylakoid membranes.

Lipid molecular species compositions of chloroplast thylakoid membranes of mesophyll cells from Spinacia oleracea, Glycine max, Oryza sativa and Zea mays and of bundle sheath cells from Zea mays have been quantitatively determined. No significant difference in the lipid molecular species composition was found among the five membrane sources. The predominant molecular species of monogalactosyldiacylglycerol was the 1-linolenoyl parallel to 2-linolenoyl species. The 1-linolenoyl parallel to 2-linoenoyl and 1-palmitoyl parallel to 2-linolenoyl species were the major molecular species of digalactosyldiacylglycerol. 6-Sulfoquinovosyldiacylglycerol was mainly composed of the palmitoyl parallel to linolenoyl and palmitoyl parallel to lineolyl species. Almost all of the C-2 position of phosphatidylglycerol were esterified with the palmitoyl or delta 3-trans-hexadecenoyl residue. The molecular species compositions of phosphatidylcholine and phosphatidylinositol were basically similar to those of membranes in non-photosynthetic tissues.